I like the fast-paced narrative style. In a way, it fits the subject matter of plain, non-questionable sadism. There isn't much need for reflection if you chose to just be bad just...because.

Now, I must admit that several things bothered me a great deal in this chapter. First, this: "It's not like anyone would understand parseltongue, but he worries anyway." Uhm, she can speak parseltongue? Why? Isn't that only a Slytherin heir sort of thing? I know you need to make her as cool and scary as you can, but this is dipping toes in Mary-Sue territory. I am sure there are ways of making Zoe appear powerful and equal to Tom without, well, giving her the SAME power as him without any explanation. Similarly, the dialogue implied that Tom was kind of the side kick. The Dark Lord is nobody's sidekick...That sort of defeats the purpose of his character as the inaccessible bunddle of psychotic, obsessive insecurities. You even have him say "sorry! (!). This is your story, of course, and hpff is here to let people get crazy and creative, but I think that changing these two parts would significantly improve the quality of the story. The rest is harsh, funny, and nuts, but the issues I just mentioned made me really stumble while reading.

I think there is a lot of potential here to indirectly - and without moral heaviness getting in the way - explore the nature of sadism and evil. If you drop making Zoe into a female Tom Riddle and, instead explore the way a character can become just as cruel and self-entitled without all the "specialness" that Voldemort had to deal with, then this could become a trully amazing story!